Metal Cutting 5 Flashcards
What is centre drilling?
This operation drills a starting hole to accurately establish its location for subsequent drilling
What is countersinking?
This is similar to Counterboring, except that the step in the hole is coneshaped for flat head screws and
bolts.
What is counterboring?
Countreboring provides a stepped hole, in which a
larger diameter follows a smaller diameter partially into the hole.
What is spotfacing?
It is used to provide a flat surface on the workpiece
in a localized area. Spotfacing is similar to milling.
What is a drill press?
A drill press is the basic drilling machine and is used when location and orientation of the hole must be controlled accurately. A drill press is composed of a base that supports a column, the column in turn supports a table.
What is a radial drilling machine?
used for large workpieces, spindle
mounts on radial arm, allowing drilling operations anywhere along the arm length. The spindle feed can be manual or automated. The table may be swiveled to enable drilling on an angle.
What is a Numerical Control drilling machine?
The spindle and table movements are controlled automatically by computer. Multiple operation can be done sequentially, such as drilling, tapping, reaming. A turret may hold multiple tools and rotate to position the required tool.
What is a multiple spindle drilling machine?
Single drive motor operates multiple spindles to cut several holes at the same time. Typically the feed rate
and speeds are the same for all drills, therefore
same (or very similar) operations can be done
simultaneously.
What is reaming?
an operation to make an existing hole dimensionally more accurate than can be obtained by drilling alone. It
also improves surface finish. Reaming can be performed manually, or on a machine (such as drilling).
What is tapping?
operation is used to produce internal threads in workpiece. A tap is a threading tool with multiple cutting teeth that can be used manually or on a machine.
How is torque reduced in tapping?
Taps are typically designed in a tapered formed (slightly inclined) to reduce the torque required for tapping
What is planing?
A simple operation of producing flat
surface, grooves or notches by cutting through
the length of workpiece. The tool cuts only during the
forward movement of the head, thus slow
operations designed for large/heavy parts,
mainly for rough cutting and low quantity
products.
What is broaching?
Multi-tooth cutting tools that makes successively deeper cuts. The total depth of material removed in one stroke is the sum of cuts by each tooth.
What is rotary broaching?
A method to produce irregular shapes without using broaching machines. . The cutting edge of the broach has a contour matching the desired final shape. The broach is mounted in a special tool holder that allows it to freely rotate.
